import 'package:flutter/material.dart';

class MyApp17 extends StatelessWidget {
  const MyApp17({super.key});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        // 导航条
        appBar: AppBar(
          title: const Text('GridView初体验',
              style: TextStyle(color: Colors.white, fontSize: 20)),
          backgroundColor: Colors.pink,
          centerTitle: true,
        ),
        // 主体区域
        // 侧轴方向上的个数是固定的(无论是否旋转屏幕)
        body: GridView(
          // 视图代理
          gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
              // 设置侧轴的个数
              crossAxisCount: 3,
              // 设置主轴的间距
              mainAxisSpacing: 10,
              // 设置侧轴的间距
              crossAxisSpacing: 10,
              // 设置宽高比
              childAspectRatio: 4 / 3),
          children: [
            Container(
              color: Colors.green,
              alignment: Alignment.center,
              child: const Text('黑马程序员1'),
            ),
            Container(
              color: Colors.pink,
              alignment: Alignment.center,
              child: const Text('黑马程序员2'),
            ),
            Container(
              color: Colors.blue,
              alignment: Alignment.center,
              child: const Text('黑马程序员3'),
            ),
            Container(
              color: Colors.yellow,
              alignment: Alignment.center,
              child: const Text('黑马程序员4'),
            ),
            Container(
              color: Colors.cyan,
              alignment: Alignment.center,
              child: const Text('黑马程序员5'),
            ),
            Container(
              color: Colors.green,
              alignment: Alignment.center,
              child: const Text('黑马程序员6'),
            )
          ],
        ));
  }
}
